Defensive publication



T DEFENSIVE PUBLICATION UNITED STATES PATENT OFFICE Published at therequest of the applicant or owner in accordance with the Notice of Apr.11, 1968, 849 O.G. 1221. Identification is by serial number of theapplication and the heading indicates the number of pages ofspecification, including claims, and of sheets oi. drawing contained inthe application as originally filed. The file of this application isavailable to the public for inspection; reproduction may be purchasedfor 130 cents per sheet.

Applications published under the Defensive Publication Program have notbeen examined as to the merits of alleged invention. The Patent Officemakes no assertion as to the novelty of the disclosed subject matter.

PUBLISHED APRIL 22, 1969 PHOTOGRAPHIIC MATERIALS STABILIZED WITH BENZENESELENINIC ACID AND TETRAAZA- INDENE ANTIFOGGANTS William Farrell Smithand Dorothy Johnson Beavers, both of Kodak Park Division, Rochester,N.Y. 14650 Filed Dec. 30, 1968. Published Apr. 22, 1969 Class 96-109 NoDrawing. 13 Pages Specification Photographic silver halide emulsions arestabilized against fog With (l) a benzene seleninic acid antifoggant,e.g., benzene seleninic acid salt or free acid and (2) a 4-hydroxy-6-alkyl-1,3,3a,7-tetraazaindene antifoggant, e.g.,4-hydroXy-6-methyl-1,3,3 a,7-tetraazaindene. Enhanced activity isobtained when the photographic emulsions or elements disclosed alsocontain a development modifier which is:

(1) a substantially non-vulcanizable linear polymer containing at leastthree linear thioether atoms and having a molecular Weight of at leastabout 250,

(2) an onium salt comprising a quaternary ammonium, quaternaryphosphonium or ternary sulfonium salt group, or

(3) an alkylene oxide polymer.

Suitable development modifiers include linear condensation products ofdiols such as 3-thiapcntane-l,S-diol with dibasic acids such as glutaricacid, 7,18-diaza6,19-dioxotetracosane 1,24 bis(pyridinium perchlorate)and oleyl ether polyethylene oxide.

Silver halide emulsions and elements stabilized as described can bechemically sensitized, e.g., with noble metal sensitizers alone or incombination With sulfur or selenium sensitizers. They can containspectral sensitizers, incorporated color-forming couplers, incorporateddeveloping agents, other antifoggants, hardeners, plasticizers, vinylpolymers, coating aids, and other suitable photographic addenda, such asdescribed in US. Patent 3,297,446 (columns 4-9).

